Face ID failed during its public debut. The reasons are up for debate, but the bottom line is Apple’s latest feature remains a question mark.

Facial recognition is a complex technology and Apple deserves credit for bringing it to the masses with its latest phone. But Face ID’s debut at yesterday’s keynote raises a touchy question: What if Face ID isn’t ready for prime time?

As Craig Federighi began his iPhone X demo yesterday, he told attendees that unlocking the phone with Face ID was “as easy as looking at it and swiping up.”

More from Barron’s Next

One problem: The phone didn’t unlock. Federighi tried unlocking with Face ID twice, was prompted for his passcode, and moved on to his “backup” iPhone, which did seem to recognize his face.

Apple touted the security benefits of using Face ID versus the prior Touch ID fingerprint sensor, saying that there was a “one in a million” chance of someone else’s face being able to unlock your phone. But Apple’s decision to use Face ID instead of Touch ID was likely the result of technological issues, too. The company reportedly had trouble embedding a fingerprint sensor behind the iPhone X’s edge-to-edge OLED screen.

It’s troubling that Face ID didn’t work the first two out of three times it was tried in the demo, because iPhone users have gotten used to unlocking their phones quickly, without doing much work, and definitely without relying on passcodes. New York Magazine suggests that the glitch wasn’t an issue with Face ID itself, but rather part of the initial boot-up process, which always requires a traditional passcode. It’s hard to imagine Apple didn’t plan for that, though, by restarting the device before the demo began.

Even if Face ID proves more reliable going forward, it’s bound to still cause issues for users. There are plenty of times when you want to unlock or authenticate your phone without staring right at it, like if you’re discreetly texting during a meeting or paying with Apple Pay at a store.

Because the iPhone X doesn’t begin shipping until November 3, it’s likely that we won’t find out how well Face ID works until the early reviews roll out in the days leading up to the release. If Face ID gets a bad rap, consumers might quickly give up on the $1,000 phone.

Luckily, they’ll have some pretty good alternatives. Apple’s iPhone 8 and 8 Plus, also announced Tuesday, boast improved processors and camera features, and they support wireless charging. They don’t have the fancy OLED screen, but that means they get to keep reliable Touch ID. And one more thing: They cost a whole lot less.

This copy is for your personal, non-commercial use only. Distribution and use of this material are governed by our Subscriber Agreement and by copyright law. For non-personal use or to order multiple copies, please contact Dow Jones Reprints at 1-800-843-0008 or visit www.djreprints.com.